Nanoparticle morphology/shape control

The control of nanoparticle morphology becomes a very important aspect, since morphology profoundly influences the material performance. As a longterm goal the development of synthesis schemes able to control particle size, shapes, and composition independently from one another is very important, in order to allow tuning of nanocomposite properties. 

Semiconducting nanorods and nanowires were synthesized by y-irradiation at room temperature and the atmospheric pressure. The experiment was carried out in ethylenediamine and pyridine as solvents. Ethylenediamine (en) and pyridine (py) molecules were coordinated with metal ions and had an effect on the shape like nanorods and nanowires (Jo et al. 2006). Semiconducting nanorod and pearl necklace-like nanowire of CdS and CdSe were successfully synthesized by irradiation with a dose of 90 kGy at room temperature and the atmospheric pressure. When nanorods and nanowires were prepared in en and py, the solvent molecules controlled their morphology. From XRD data, the synthesized CdS and CdSe could be observed on the information of crystallinity of them. In nanorod CdS and CdSe, the intensity of the (0 0 2) diffraction peak was extraordinarily strong. This result indicates that the CdS obtained in py have a preferential [0 0 1] orientation. TEM images displayed rod and pearl necklace like morphology with diameters of several nanometers and lengths of upto several microns. For the shape control, en and py were successfully used to replace the surfactant molecules on the surface of nanoparticles. 

Scotti, R., Conzatti, L., D Arienzo, M., Di Ctedico, B., Giannini, L., Hand, T., Stagnaro, P., Susanna, A., Tadiello, L., Morazzoni, F. Shape controlled spherical (OD) and rod-Uke (ID) silica nanoparticles in silica/styrene butadiene rubber nanocomposites role of the particle morphology on the fillta- reinfradng effect. Polymer 55, 1497-1506 (2014)... 

The shape control of nanoparticles is a very important aspect in nanotechnology, due to the spectacular effects that structural anisotropy may have on many of the material s physical properties. Because of these size- and shape-dependent properties, much effort has been expended in controlling the morphology and assembly of nanoparticles [68-69]. The most common architecture of these nanocrystals is isotropic particles, ranging from spherical to highly faceted particles, such as cubic and octahedral. One-dimensional (1-D) anisotropic nanoparticles include uniform rods and wires, whereas two-dimensional (2-D) nanoparticles consists of nanodiscs, plates and other advanced shapes such as rod-based multipods and nanostars. 

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